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function A = frand (n,nel,s)
% A = frand (n,nel,s) creates an n-by-n sparse matrix consisting of nel finite
% elements, each of which are of size s-by-s with random symmetric nonzero
% pattern, plus the identity matrix.
%
% Example:
% A = frand (100, 100, 4) ; cspy (A)
% See also: cs_demo
% Copyright 2006-2012, Timothy A. Davis, http://www.suitesparse.com
ss = s^2 ;
nz = nel*ss ;
ii = zeros (nz,1) ;
jj = zeros (nz,1) ;
xx = zeros (nz,1) ;
k = 1 ;
for e = 1:nel
i = 1 + fix (n * rand (s,1)) ;
i = repmat (i, 1, s) ;
j = i' ;
x = rand (s,s) ;
ii (k:k+ss-1) = i (:) ;
jj (k:k+ss-1) = j (:) ;
xx (k:k+ss-1) = x (:) ;
k = k + ss ;
end
A = sparse (ii,jj,xx,n,n) + speye (n) ;
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